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<pre><span class="sourceLineNo">001</span>/*<a name="line.1"></a>
<span class="sourceLineNo">002</span> * Copyright (C) 2009 The Guava Authors<a name="line.2"></a>
<span class="sourceLineNo">003</span> *<a name="line.3"></a>
<span class="sourceLineNo">004</span> * Licensed under the Apache License, Version 2.0 (the "License");<a name="line.4"></a>
<span class="sourceLineNo">005</span> * you may not use this file except in compliance with the License.<a name="line.5"></a>
<span class="sourceLineNo">006</span> * You may obtain a copy of the License at<a name="line.6"></a>
<span class="sourceLineNo">007</span> *<a name="line.7"></a>
<span class="sourceLineNo">008</span> * http://www.apache.org/licenses/LICENSE-2.0<a name="line.8"></a>
<span class="sourceLineNo">009</span> *<a name="line.9"></a>
<span class="sourceLineNo">010</span> * Unless required by applicable law or agreed to in writing, software<a name="line.10"></a>
<span class="sourceLineNo">011</span> * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.11"></a>
<span class="sourceLineNo">012</span> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.12"></a>
<span class="sourceLineNo">013</span> * See the License for the specific language governing permissions and<a name="line.13"></a>
<span class="sourceLineNo">014</span> * limitations under the License.<a name="line.14"></a>
<span class="sourceLineNo">015</span> */<a name="line.15"></a>
<span class="sourceLineNo">016</span><a name="line.16"></a>
<span class="sourceLineNo">017</span>package com.google.common.util.concurrent;<a name="line.17"></a>
<span class="sourceLineNo">018</span><a name="line.18"></a>
<span class="sourceLineNo">019</span>import static com.google.common.base.Preconditions.checkArgument;<a name="line.19"></a>
<span class="sourceLineNo">020</span>import static com.google.common.base.Preconditions.checkNotNull;<a name="line.20"></a>
<span class="sourceLineNo">021</span>import static com.google.common.base.Preconditions.checkState;<a name="line.21"></a>
<span class="sourceLineNo">022</span><a name="line.22"></a>
<span class="sourceLineNo">023</span>import com.google.common.annotations.Beta;<a name="line.23"></a>
<span class="sourceLineNo">024</span>import com.google.common.collect.Lists;<a name="line.24"></a>
<span class="sourceLineNo">025</span>import com.google.common.collect.Queues;<a name="line.25"></a>
<span class="sourceLineNo">026</span>import com.google.common.util.concurrent.Service.State; // javadoc needs this<a name="line.26"></a>
<span class="sourceLineNo">027</span><a name="line.27"></a>
<span class="sourceLineNo">028</span>import java.util.List;<a name="line.28"></a>
<span class="sourceLineNo">029</span>import java.util.Queue;<a name="line.29"></a>
<span class="sourceLineNo">030</span>import java.util.concurrent.ExecutionException;<a name="line.30"></a>
<span class="sourceLineNo">031</span>import java.util.concurrent.Executor;<a name="line.31"></a>
<span class="sourceLineNo">032</span>import java.util.concurrent.TimeUnit;<a name="line.32"></a>
<span class="sourceLineNo">033</span>import java.util.concurrent.TimeoutException;<a name="line.33"></a>
<span class="sourceLineNo">034</span>import java.util.concurrent.locks.ReentrantLock;<a name="line.34"></a>
<span class="sourceLineNo">035</span>import java.util.logging.Level;<a name="line.35"></a>
<span class="sourceLineNo">036</span>import java.util.logging.Logger;<a name="line.36"></a>
<span class="sourceLineNo">037</span><a name="line.37"></a>
<span class="sourceLineNo">038</span>import javax.annotation.Nullable;<a name="line.38"></a>
<span class="sourceLineNo">039</span>import javax.annotation.concurrent.GuardedBy;<a name="line.39"></a>
<span class="sourceLineNo">040</span>import javax.annotation.concurrent.Immutable;<a name="line.40"></a>
<span class="sourceLineNo">041</span><a name="line.41"></a>
<span class="sourceLineNo">042</span>/**<a name="line.42"></a>
<span class="sourceLineNo">043</span> * Base class for implementing services that can handle {@link #doStart} and {@link #doStop}<a name="line.43"></a>
<span class="sourceLineNo">044</span> * requests, responding to them with {@link #notifyStarted()} and {@link #notifyStopped()}<a name="line.44"></a>
<span class="sourceLineNo">045</span> * callbacks. Its subclasses must manage threads manually; consider<a name="line.45"></a>
<span class="sourceLineNo">046</span> * {@link AbstractExecutionThreadService} if you need only a single execution thread.<a name="line.46"></a>
<span class="sourceLineNo">047</span> *<a name="line.47"></a>
<span class="sourceLineNo">048</span> * @author Jesse Wilson<a name="line.48"></a>
<span class="sourceLineNo">049</span> * @author Luke Sandberg<a name="line.49"></a>
<span class="sourceLineNo">050</span> * @since 1.0<a name="line.50"></a>
<span class="sourceLineNo">051</span> */<a name="line.51"></a>
<span class="sourceLineNo">052</span>@Beta<a name="line.52"></a>
<span class="sourceLineNo">053</span>public abstract class AbstractService implements Service {<a name="line.53"></a>
<span class="sourceLineNo">054</span>  private static final Logger logger = Logger.getLogger(AbstractService.class.getName());<a name="line.54"></a>
<span class="sourceLineNo">055</span>  private final ReentrantLock lock = new ReentrantLock();<a name="line.55"></a>
<span class="sourceLineNo">056</span><a name="line.56"></a>
<span class="sourceLineNo">057</span>  private final Transition startup = new Transition();<a name="line.57"></a>
<span class="sourceLineNo">058</span>  private final Transition shutdown = new Transition();<a name="line.58"></a>
<span class="sourceLineNo">059</span><a name="line.59"></a>
<span class="sourceLineNo">060</span>  /**<a name="line.60"></a>
<span class="sourceLineNo">061</span>   * The listeners to notify during a state transition.<a name="line.61"></a>
<span class="sourceLineNo">062</span>   */<a name="line.62"></a>
<span class="sourceLineNo">063</span>  @GuardedBy("lock")<a name="line.63"></a>
<span class="sourceLineNo">064</span>  private final List&lt;ListenerExecutorPair&gt; listeners = Lists.newArrayList();<a name="line.64"></a>
<span class="sourceLineNo">065</span><a name="line.65"></a>
<span class="sourceLineNo">066</span>  /**<a name="line.66"></a>
<span class="sourceLineNo">067</span>   * The queue of listeners that are waiting to be executed.<a name="line.67"></a>
<span class="sourceLineNo">068</span>   *<a name="line.68"></a>
<span class="sourceLineNo">069</span>   * &lt;p&gt;Enqueue operations should be protected by {@link #lock} while dequeue operations should be<a name="line.69"></a>
<span class="sourceLineNo">070</span>   * protected by the implicit lock on this object. Dequeue operations should be executed atomically<a name="line.70"></a>
<span class="sourceLineNo">071</span>   * with the execution of the {@link Runnable} and additionally the {@link #lock} should not be<a name="line.71"></a>
<span class="sourceLineNo">072</span>   * held when the listeners are being executed. Use {@link #executeListeners} for this operation.<a name="line.72"></a>
<span class="sourceLineNo">073</span>   * This is necessary to ensure that elements on the queue are executed in the correct order.<a name="line.73"></a>
<span class="sourceLineNo">074</span>   * Enqueue operations should be protected so that listeners are added in the correct order. We use<a name="line.74"></a>
<span class="sourceLineNo">075</span>   * a concurrent queue implementation so that enqueues can be executed concurrently with dequeues.<a name="line.75"></a>
<span class="sourceLineNo">076</span>   */<a name="line.76"></a>
<span class="sourceLineNo">077</span>  @GuardedBy("queuedListeners")<a name="line.77"></a>
<span class="sourceLineNo">078</span>  private final Queue&lt;Runnable&gt; queuedListeners = Queues.newConcurrentLinkedQueue();<a name="line.78"></a>
<span class="sourceLineNo">079</span><a name="line.79"></a>
<span class="sourceLineNo">080</span>  /**<a name="line.80"></a>
<span class="sourceLineNo">081</span>   * The current state of the service.  This should be written with the lock held but can be read<a name="line.81"></a>
<span class="sourceLineNo">082</span>   * without it because it is an immutable object in a volatile field.  This is desirable so that<a name="line.82"></a>
<span class="sourceLineNo">083</span>   * methods like {@link #state}, {@link #failureCause} and notably {@link #toString} can be run<a name="line.83"></a>
<span class="sourceLineNo">084</span>   * without grabbing the lock.<a name="line.84"></a>
<span class="sourceLineNo">085</span>   *<a name="line.85"></a>
<span class="sourceLineNo">086</span>   * &lt;p&gt;To update this field correctly the lock must be held to guarantee that the state is<a name="line.86"></a>
<span class="sourceLineNo">087</span>   * consistent.<a name="line.87"></a>
<span class="sourceLineNo">088</span>   */<a name="line.88"></a>
<span class="sourceLineNo">089</span>  @GuardedBy("lock")<a name="line.89"></a>
<span class="sourceLineNo">090</span>  private volatile StateSnapshot snapshot = new StateSnapshot(State.NEW);<a name="line.90"></a>
<span class="sourceLineNo">091</span><a name="line.91"></a>
<span class="sourceLineNo">092</span>  /** Constructor for use by subclasses. */<a name="line.92"></a>
<span class="sourceLineNo">093</span>  protected AbstractService() {<a name="line.93"></a>
<span class="sourceLineNo">094</span>    // Add a listener to update the futures. This needs to be added first so that it is executed<a name="line.94"></a>
<span class="sourceLineNo">095</span>    // before the other listeners. This way the other listeners can access the completed futures.<a name="line.95"></a>
<span class="sourceLineNo">096</span>    addListener(<a name="line.96"></a>
<span class="sourceLineNo">097</span>        new Listener() {<a name="line.97"></a>
<span class="sourceLineNo">098</span>          @Override public void starting() {}<a name="line.98"></a>
<span class="sourceLineNo">099</span><a name="line.99"></a>
<span class="sourceLineNo">100</span>          @Override public void running() {<a name="line.100"></a>
<span class="sourceLineNo">101</span>            startup.set(State.RUNNING);<a name="line.101"></a>
<span class="sourceLineNo">102</span>          }<a name="line.102"></a>
<span class="sourceLineNo">103</span><a name="line.103"></a>
<span class="sourceLineNo">104</span>          @Override public void stopping(State from) {<a name="line.104"></a>
<span class="sourceLineNo">105</span>            if (from == State.STARTING) {<a name="line.105"></a>
<span class="sourceLineNo">106</span>              startup.set(State.STOPPING);<a name="line.106"></a>
<span class="sourceLineNo">107</span>            }<a name="line.107"></a>
<span class="sourceLineNo">108</span>          }<a name="line.108"></a>
<span class="sourceLineNo">109</span><a name="line.109"></a>
<span class="sourceLineNo">110</span>          @Override public void terminated(State from) {<a name="line.110"></a>
<span class="sourceLineNo">111</span>            if (from == State.NEW) {<a name="line.111"></a>
<span class="sourceLineNo">112</span>              startup.set(State.TERMINATED);<a name="line.112"></a>
<span class="sourceLineNo">113</span>            }<a name="line.113"></a>
<span class="sourceLineNo">114</span>            shutdown.set(State.TERMINATED);<a name="line.114"></a>
<span class="sourceLineNo">115</span>          }<a name="line.115"></a>
<span class="sourceLineNo">116</span><a name="line.116"></a>
<span class="sourceLineNo">117</span>          @Override public void failed(State from, Throwable failure) {<a name="line.117"></a>
<span class="sourceLineNo">118</span>            switch (from) {<a name="line.118"></a>
<span class="sourceLineNo">119</span>              case STARTING:<a name="line.119"></a>
<span class="sourceLineNo">120</span>                startup.setException(failure);<a name="line.120"></a>
<span class="sourceLineNo">121</span>                shutdown.setException(new Exception("Service failed to start.", failure));<a name="line.121"></a>
<span class="sourceLineNo">122</span>                break;<a name="line.122"></a>
<span class="sourceLineNo">123</span>              case RUNNING:<a name="line.123"></a>
<span class="sourceLineNo">124</span>                shutdown.setException(new Exception("Service failed while running", failure));<a name="line.124"></a>
<span class="sourceLineNo">125</span>                break;<a name="line.125"></a>
<span class="sourceLineNo">126</span>              case STOPPING:<a name="line.126"></a>
<span class="sourceLineNo">127</span>                shutdown.setException(failure);<a name="line.127"></a>
<span class="sourceLineNo">128</span>                break;<a name="line.128"></a>
<span class="sourceLineNo">129</span>              case TERMINATED:  /* fall-through */<a name="line.129"></a>
<span class="sourceLineNo">130</span>              case FAILED:  /* fall-through */<a name="line.130"></a>
<span class="sourceLineNo">131</span>              case NEW:  /* fall-through */<a name="line.131"></a>
<span class="sourceLineNo">132</span>              default:<a name="line.132"></a>
<span class="sourceLineNo">133</span>                throw new AssertionError("Unexpected from state: " + from);<a name="line.133"></a>
<span class="sourceLineNo">134</span>            }<a name="line.134"></a>
<span class="sourceLineNo">135</span>          }<a name="line.135"></a>
<span class="sourceLineNo">136</span>        },<a name="line.136"></a>
<span class="sourceLineNo">137</span>        MoreExecutors.sameThreadExecutor());<a name="line.137"></a>
<span class="sourceLineNo">138</span>  }<a name="line.138"></a>
<span class="sourceLineNo">139</span><a name="line.139"></a>
<span class="sourceLineNo">140</span>  /**<a name="line.140"></a>
<span class="sourceLineNo">141</span>   * This method is called by {@link #start} to initiate service startup. The invocation of this<a name="line.141"></a>
<span class="sourceLineNo">142</span>   * method should cause a call to {@link #notifyStarted()}, either during this method's run, or<a name="line.142"></a>
<span class="sourceLineNo">143</span>   * after it has returned. If startup fails, the invocation should cause a call to<a name="line.143"></a>
<span class="sourceLineNo">144</span>   * {@link #notifyFailed(Throwable)} instead.<a name="line.144"></a>
<span class="sourceLineNo">145</span>   *<a name="line.145"></a>
<span class="sourceLineNo">146</span>   * &lt;p&gt;This method should return promptly; prefer to do work on a different thread where it is<a name="line.146"></a>
<span class="sourceLineNo">147</span>   * convenient. It is invoked exactly once on service startup, even when {@link #start} is called<a name="line.147"></a>
<span class="sourceLineNo">148</span>   * multiple times.<a name="line.148"></a>
<span class="sourceLineNo">149</span>   */<a name="line.149"></a>
<span class="sourceLineNo">150</span>  protected abstract void doStart();<a name="line.150"></a>
<span class="sourceLineNo">151</span><a name="line.151"></a>
<span class="sourceLineNo">152</span>  /**<a name="line.152"></a>
<span class="sourceLineNo">153</span>   * This method should be used to initiate service shutdown. The invocation of this method should<a name="line.153"></a>
<span class="sourceLineNo">154</span>   * cause a call to {@link #notifyStopped()}, either during this method's run, or after it has<a name="line.154"></a>
<span class="sourceLineNo">155</span>   * returned. If shutdown fails, the invocation should cause a call to<a name="line.155"></a>
<span class="sourceLineNo">156</span>   * {@link #notifyFailed(Throwable)} instead.<a name="line.156"></a>
<span class="sourceLineNo">157</span>   *<a name="line.157"></a>
<span class="sourceLineNo">158</span>   * &lt;p&gt; This method should return promptly; prefer to do work on a different thread where it is<a name="line.158"></a>
<span class="sourceLineNo">159</span>   * convenient. It is invoked exactly once on service shutdown, even when {@link #stop} is called<a name="line.159"></a>
<span class="sourceLineNo">160</span>   * multiple times.<a name="line.160"></a>
<span class="sourceLineNo">161</span>   */<a name="line.161"></a>
<span class="sourceLineNo">162</span>  protected abstract void doStop();<a name="line.162"></a>
<span class="sourceLineNo">163</span><a name="line.163"></a>
<span class="sourceLineNo">164</span>  @Override<a name="line.164"></a>
<span class="sourceLineNo">165</span>  public final ListenableFuture&lt;State&gt; start() {<a name="line.165"></a>
<span class="sourceLineNo">166</span>    lock.lock();<a name="line.166"></a>
<span class="sourceLineNo">167</span>    try {<a name="line.167"></a>
<span class="sourceLineNo">168</span>      if (snapshot.state == State.NEW) {<a name="line.168"></a>
<span class="sourceLineNo">169</span>        snapshot = new StateSnapshot(State.STARTING);<a name="line.169"></a>
<span class="sourceLineNo">170</span>        starting();<a name="line.170"></a>
<span class="sourceLineNo">171</span>        doStart();<a name="line.171"></a>
<span class="sourceLineNo">172</span>      }<a name="line.172"></a>
<span class="sourceLineNo">173</span>    } catch (Throwable startupFailure) {<a name="line.173"></a>
<span class="sourceLineNo">174</span>      notifyFailed(startupFailure);<a name="line.174"></a>
<span class="sourceLineNo">175</span>    } finally {<a name="line.175"></a>
<span class="sourceLineNo">176</span>      lock.unlock();<a name="line.176"></a>
<span class="sourceLineNo">177</span>      executeListeners();<a name="line.177"></a>
<span class="sourceLineNo">178</span>    }<a name="line.178"></a>
<span class="sourceLineNo">179</span><a name="line.179"></a>
<span class="sourceLineNo">180</span>    return startup;<a name="line.180"></a>
<span class="sourceLineNo">181</span>  }<a name="line.181"></a>
<span class="sourceLineNo">182</span><a name="line.182"></a>
<span class="sourceLineNo">183</span>  @Override<a name="line.183"></a>
<span class="sourceLineNo">184</span>  public final ListenableFuture&lt;State&gt; stop() {<a name="line.184"></a>
<span class="sourceLineNo">185</span>    lock.lock();<a name="line.185"></a>
<span class="sourceLineNo">186</span>    try {<a name="line.186"></a>
<span class="sourceLineNo">187</span>      switch (snapshot.state) {<a name="line.187"></a>
<span class="sourceLineNo">188</span>        case NEW:<a name="line.188"></a>
<span class="sourceLineNo">189</span>          snapshot = new StateSnapshot(State.TERMINATED);<a name="line.189"></a>
<span class="sourceLineNo">190</span>          terminated(State.NEW);<a name="line.190"></a>
<span class="sourceLineNo">191</span>          break;<a name="line.191"></a>
<span class="sourceLineNo">192</span>        case STARTING:<a name="line.192"></a>
<span class="sourceLineNo">193</span>          snapshot = new StateSnapshot(State.STARTING, true, null);<a name="line.193"></a>
<span class="sourceLineNo">194</span>          stopping(State.STARTING);<a name="line.194"></a>
<span class="sourceLineNo">195</span>          break;<a name="line.195"></a>
<span class="sourceLineNo">196</span>        case RUNNING:<a name="line.196"></a>
<span class="sourceLineNo">197</span>          snapshot = new StateSnapshot(State.STOPPING);<a name="line.197"></a>
<span class="sourceLineNo">198</span>          stopping(State.RUNNING);<a name="line.198"></a>
<span class="sourceLineNo">199</span>          doStop();<a name="line.199"></a>
<span class="sourceLineNo">200</span>          break;<a name="line.200"></a>
<span class="sourceLineNo">201</span>        case STOPPING:<a name="line.201"></a>
<span class="sourceLineNo">202</span>        case TERMINATED:<a name="line.202"></a>
<span class="sourceLineNo">203</span>        case FAILED:<a name="line.203"></a>
<span class="sourceLineNo">204</span>          // do nothing<a name="line.204"></a>
<span class="sourceLineNo">205</span>          break;<a name="line.205"></a>
<span class="sourceLineNo">206</span>        default:<a name="line.206"></a>
<span class="sourceLineNo">207</span>          throw new AssertionError("Unexpected state: " + snapshot.state);<a name="line.207"></a>
<span class="sourceLineNo">208</span>      }<a name="line.208"></a>
<span class="sourceLineNo">209</span>    } catch (Throwable shutdownFailure) {<a name="line.209"></a>
<span class="sourceLineNo">210</span>      notifyFailed(shutdownFailure);<a name="line.210"></a>
<span class="sourceLineNo">211</span>    } finally {<a name="line.211"></a>
<span class="sourceLineNo">212</span>      lock.unlock();<a name="line.212"></a>
<span class="sourceLineNo">213</span>      executeListeners();<a name="line.213"></a>
<span class="sourceLineNo">214</span>    }<a name="line.214"></a>
<span class="sourceLineNo">215</span><a name="line.215"></a>
<span class="sourceLineNo">216</span>    return shutdown;<a name="line.216"></a>
<span class="sourceLineNo">217</span>  }<a name="line.217"></a>
<span class="sourceLineNo">218</span><a name="line.218"></a>
<span class="sourceLineNo">219</span>  @Override<a name="line.219"></a>
<span class="sourceLineNo">220</span>  public State startAndWait() {<a name="line.220"></a>
<span class="sourceLineNo">221</span>    return Futures.getUnchecked(start());<a name="line.221"></a>
<span class="sourceLineNo">222</span>  }<a name="line.222"></a>
<span class="sourceLineNo">223</span><a name="line.223"></a>
<span class="sourceLineNo">224</span>  @Override<a name="line.224"></a>
<span class="sourceLineNo">225</span>  public State stopAndWait() {<a name="line.225"></a>
<span class="sourceLineNo">226</span>    return Futures.getUnchecked(stop());<a name="line.226"></a>
<span class="sourceLineNo">227</span>  }<a name="line.227"></a>
<span class="sourceLineNo">228</span><a name="line.228"></a>
<span class="sourceLineNo">229</span>  /**<a name="line.229"></a>
<span class="sourceLineNo">230</span>   * Implementing classes should invoke this method once their service has started. It will cause<a name="line.230"></a>
<span class="sourceLineNo">231</span>   * the service to transition from {@link State#STARTING} to {@link State#RUNNING}.<a name="line.231"></a>
<span class="sourceLineNo">232</span>   *<a name="line.232"></a>
<span class="sourceLineNo">233</span>   * @throws IllegalStateException if the service is not {@link State#STARTING}.<a name="line.233"></a>
<span class="sourceLineNo">234</span>   */<a name="line.234"></a>
<span class="sourceLineNo">235</span>  protected final void notifyStarted() {<a name="line.235"></a>
<span class="sourceLineNo">236</span>    lock.lock();<a name="line.236"></a>
<span class="sourceLineNo">237</span>    try {<a name="line.237"></a>
<span class="sourceLineNo">238</span>      if (snapshot.state != State.STARTING) {<a name="line.238"></a>
<span class="sourceLineNo">239</span>        IllegalStateException failure = new IllegalStateException(<a name="line.239"></a>
<span class="sourceLineNo">240</span>            "Cannot notifyStarted() when the service is " + snapshot.state);<a name="line.240"></a>
<span class="sourceLineNo">241</span>        notifyFailed(failure);<a name="line.241"></a>
<span class="sourceLineNo">242</span>        throw failure;<a name="line.242"></a>
<span class="sourceLineNo">243</span>      }<a name="line.243"></a>
<span class="sourceLineNo">244</span><a name="line.244"></a>
<span class="sourceLineNo">245</span>      if (snapshot.shutdownWhenStartupFinishes) {<a name="line.245"></a>
<span class="sourceLineNo">246</span>        snapshot = new StateSnapshot(State.STOPPING);<a name="line.246"></a>
<span class="sourceLineNo">247</span>        // We don't call listeners here because we already did that when we set the<a name="line.247"></a>
<span class="sourceLineNo">248</span>        // shutdownWhenStartupFinishes flag.<a name="line.248"></a>
<span class="sourceLineNo">249</span>        doStop();<a name="line.249"></a>
<span class="sourceLineNo">250</span>      } else {<a name="line.250"></a>
<span class="sourceLineNo">251</span>        snapshot = new StateSnapshot(State.RUNNING);<a name="line.251"></a>
<span class="sourceLineNo">252</span>        running();<a name="line.252"></a>
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<span class="sourceLineNo">261</span>   * Implementing classes should invoke this method once their service has stopped. It will cause<a name="line.261"></a>
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<span class="sourceLineNo">286</span>   * Invoke this method to transition the service to the {@link State#FAILED}. The service will<a name="line.286"></a>
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<span class="sourceLineNo">516</span>          + "instead.", internalState, failure);<a name="line.516"></a>
<span class="sourceLineNo">517</span>      this.state = internalState;<a name="line.517"></a>
<span class="sourceLineNo">518</span>      this.shutdownWhenStartupFinishes = shutdownWhenStartupFinishes;<a name="line.518"></a>
<span class="sourceLineNo">519</span>      this.failure = failure;<a name="line.519"></a>
<span class="sourceLineNo">520</span>    }<a name="line.520"></a>
<span class="sourceLineNo">521</span><a name="line.521"></a>
<span class="sourceLineNo">522</span>    /** @see Service#state() */<a name="line.522"></a>
<span class="sourceLineNo">523</span>    State externalState() {<a name="line.523"></a>
<span class="sourceLineNo">524</span>      if (shutdownWhenStartupFinishes &amp;&amp; state == State.STARTING) {<a name="line.524"></a>
<span class="sourceLineNo">525</span>        return State.STOPPING;<a name="line.525"></a>
<span class="sourceLineNo">526</span>      } else {<a name="line.526"></a>
<span class="sourceLineNo">527</span>        return state;<a name="line.527"></a>
<span class="sourceLineNo">528</span>      }<a name="line.528"></a>
<span class="sourceLineNo">529</span>    }<a name="line.529"></a>
<span class="sourceLineNo">530</span><a name="line.530"></a>
<span class="sourceLineNo">531</span>    /** @see Service#failureCause() */<a name="line.531"></a>
<span class="sourceLineNo">532</span>    Throwable failureCause() {<a name="line.532"></a>
<span class="sourceLineNo">533</span>      checkState(state == State.FAILED,<a name="line.533"></a>
<span class="sourceLineNo">534</span>          "failureCause() is only valid if the service has failed, service is %s", state);<a name="line.534"></a>
<span class="sourceLineNo">535</span>      return failure;<a name="line.535"></a>
<span class="sourceLineNo">536</span>    }<a name="line.536"></a>
<span class="sourceLineNo">537</span>  }<a name="line.537"></a>
<span class="sourceLineNo">538</span>}<a name="line.538"></a>




























































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